Conclusion from Speaker 1:
Around 30% of Indonesia’s territory consists of soft soil that hampers accessibility, thus requiring innovative construction methods to improve soil bearing capacity. One popular solution is Geofoam (EPS), a lightweight material easily applied without compaction and effective in floating construction methods such as box culverts. Geofoam works with Newton’s and Archimedes’ principles to distribute loads and resist buoyancy, and has been proven through durability and simulation tests to enhance soil capacity. However, because of its lightweight properties, proper planning and installation are crucial to prevent deformation or structural degradation, ensuring Geofoam becomes a truly effective solution for infrastructure development on soft soil.

Theme: Application of Post-Installed Anchor Technology in Buildings

Speaker: Dana Luthfi Ilmansyah, S.T., M.Sc. (Engineering, Project Manager, and Production Expert, PT. Hilti Nusantara)

1. Anchoring and Its Benefits in Construction

• Anchoring is the process of installing fastening elements (anchors) to transfer loads from structural or non-structural elements to a base material (commonly concrete, steel, or masonry). The anchoring method is chosen according to purpose and necessity, to ensure stronger structural performance against vibration and optimal load distribution.

2. Anchoring Methods
   Anchoring or fastening can be divided into two categories:

• Cast-in-place fastening, where bolts are embedded before concrete pouring, allowing integration and strengthening.

• Post-installed fastening, where anchors are fixed after the concrete has hardened, either with chemical adhesives or mechanical systems.

3. Disadvantages of Cast-in-place Anchors:

• Hilti engineers reported issues such as misaligned bolts and material deformation, which can delay project schedules by 1–15%.

4. Why Post-installed Anchors Are Preferred:

• Due to the risks and uncertainties associated with cast-in-place anchors, which are difficult to correct, many architects and engineers prefer post-installed anchors.

5. Post-installed Anchor Mechanisms: Post-installed anchors work through several mechanisms:

• Friction – load is transferred through friction between the anchor rod and base material, with expansion to maximize grip.

• Keying – expansion of anchor diameter at specific points creates a mechanical lock.

• Bonding – adhesive resin bonds the anchor to the base material, with microkeying ensuring stability. Bonding + Friction – a combination of adhesive bonding and torque-induced expansion, further enhancing microkeying effects for maximum load capacity.

6. Chemical vs. Mechanical Anchors:

• Chemical anchors: offer flexibility in embedment depth and higher load capacity, but require curing time, have a more complex installation process, and are inefficient for light loads.

• Mechanical anchors: can be loaded immediately after installation, are easier to install, and suitable for light to heavy loads, but have limited embedment depth, confusing variety, and generally lower load capacity than chemical anchors.

7. Temporary Support in Construction:

• In industries such as cable tray installation, temporary support solutions like screw anchors are used to provide short-term structural stability during construction.

8. Enhancing Reinforcement with Chemical Anchors: 

• By applying resin-based adhesives, reinforcing bars, threaded rods, or bolts can be securely bonded to concrete, improving structural performance through strong bonding action.

9. The Importance of Proper Anchor Design and Application:

• Incorrect anchor design or installation can be fatal, causing faulty sections and critical cracks that compromise building integrity and may even result in partial or total collapse.

Speakers:

1. Prof. Dr. Ir. Juni Gultom, S.T., MTP. (Acting Regional Secretary, Kotawaringin Barat Regency)

2. Dana Luthfi Ilmansyah, S.T., M.Sc. (Engineering, Project Manager, and Production Expert, PT. Hilti Nusantara)

Moderator:
Mrs. Isfandina, S.T., M.T. – Lecturer, Civil Engineering Program, Universitas Dian Nusantara